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Have "down flow" furnace--is modulating gas furnace ok?

I have 2 estimates so far. 1 is for York Affinity 80% efficiency modulating gas furnace and Latitude 80% single speed. The other is for Goodman 80% single speed and he told me a "2 stage" is not available for me because I have a"down flow" furnace system.
This is still confusing to me. Is a "2 stage" the same as a "modulating"? Any suggestions or explanations?

If you can afford it get a furnace with an efficiency higher than 80&#37; otherwise you throw away an extra 10% on you utility bills. Also IMO honeywell visionpro 8000 thermostat and depending on where you live the one with humidity control for winter(and a humidifier). Some people here like Goodman so I willnot give my op on them but if you do go with Goodman(or any other brand for that matter) be sure it is purchased from a local dealer otherwise you may have warranty nightmares

I have 2 estimates so far. 1 is for York Affinity 80% efficiency modulating gas furnace and Latitude 80% single speed. The other is for Goodman 80% single speed and he told me a "2 stage" is not available for me because I have a"down flow" furnace system.
This is still confusing to me. Is a "2 stage" the same as a "modulating"? Any suggestions or explanations?

There is no rule that forbids 2 stage or modulating in a downflow. However not every manufacturer makes every combination of orientation versus feature.

If you can't get what you want in York or Goodman, try Ruud/Rheem, their modulating furnace is available in downflow. I have the (essentially identical) upflow version and am quite pleased with it.

You don't get better efficiency from a mod. York has 95% efficiecnt 2 stage, and a 95% mod.
The mod is just for increased comfort.

increased pain in the ass! really i think that modulating furnaces may catch on, but they like every modern geothermal hp i see, are extremely over engineered!!! seriously 300-600$ control boards?...not to mention how much vs motors cost! i ve installed/serviced only a few(thankfully) of these units and really,.. its confusing.also depending on the install,new construction vs. retrofit,(even though the whole comfort thing is the main selling point) setting them up is a vague process. in my opinion a two stage 95+ furnace is the way to go. especially with an hp!

The board for Rheem's Mod costs us 10% more than the board for a single stage Carrier 80/90. The modulating gas valve isn't that pricey, nor is the 2 speed inducer. Otherwise just the ECM motor like any high end furnace and the usual furnace components. Be sure to put an extended warranty on it, just like you should any furnace sale. They are all troublesome these days.